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New Member

Can't get switch ports to work

Okay so I have a basic home lab, 2600 router x2 and 2900 XL switch x 2. I've connected each router together (they "see" each other in cdp), and each router to one switch. My problem is that the interfaces that the router connects to the switch won't accept an ip address, (it says unrecognized command) and the switch lights are off). A "show status" says only the trunk port (22 on each switch) are connected. I've checked the cabling, it works, and the cables are out of the box. What am I missing/forgetting?

Sorry if i newb :\ I'm Looking forward to going over static routes xD



(I looked throught the documentation, maybe I missed it? I did a config reset on the switches. I bought these used, I hope they aren't broken :\)

New Member

Re: Can't get switch ports to work


be sure to use the correct cabling: crossover between the routers directly, and a normal patch cable to the switches.

Which interface won't accept an IP address? The Router interface or Switch interface? Could you show us the config?

Note the switch IP is configured on the VLAN interface, not the switchport interface


New Member

Re: Can't get switch ports to work

The routers are connected via serial 0, so I could do some practice frame-relay config. The routers hook up via Ethernet 0 to the switches Fast 24. (One router per switch.)

The switch interfaces will not accept an ip address (the cabling is correct), but port 22 on each switch (which is a trunk between both switches) is connected and up. When I do a show status, ports 1-21 + 23 - 24 are "not connected" according to a "show status".

I'm typing in the CLI:

Switch(config-if)# ip address

to set ip address on the ports is that the correct place to assign an ip address for ports?



New Member

Re: Can't get switch ports to work

Hi Devlin,

the 2900XL is a layer 2 switch, so you cant assign an IP address to the switchport. You need to assign it on the VLAN interface. e.g.

interface VLAN1

ip address x.x.x.x y.y.y.y

no shutdown

now you assign port fa 24 to VLAN1 by typing "switchport access vlan 1" at the switchport. Switchport are members of VLAN1 by default.

You also need to type "ip default-gateway z.z.z.z" in global config, where z.z.z.z is the address of one of your routers.

The reason why the interface is not connected might be the port being shutdown...try a no shutdown on interface fa 24. By default the ports shut come up though except if manually shut down.

Other reasons might be speed/duplex mismatch or faulty cable or port.



P.S. for switch configuration check out:


Re: Can't get switch ports to work

Check your switches, hook up your console cable and watch it boot up , if all is working ok it should end up at a "switch> prompt .

Using a straight thru cable from router to switch correct ? Make sure switchports are not admin down , not likely if you defaulted the config though.

New Member

Re: Can't get switch ports to work

No, they don't work, POST is fine (The switches boot normally), CABLING IS FINE, they are NOT admin down

Switch1#sho run

Building configuration...

Current configuration:


version 12.0

no service pad

service timestamps debug uptime

service timestamps log uptime

no service password-encryption


hostname Switch1


ip subnet-zero

!!!!! Omitted fa ports 1-24

interface VLAN1

no ip directed-broadcast

no ip route-cache


line con 0

transport input none

stopbits 1

line vty 5 15



Switch1#sho int status

Says every port except the ports trunking between the two switches is "not connected"


Switch1#sho int fa0/1

FastEthernet0/1 is down, line protocol is down

Hardware is Fast Ethernet, address is 00b0.647f.6681 (bia 00b0.647f.6681)

MTU 1500 bytes, BW 100000 Kbit, DLY 100 usec, reliability 255/255, txload 1/255, rxload 1/255 Encapsulation ARPA, loopback not set Keepalive not set Auto-duplex , Auto Speed , 100BaseTX/FX ARP type: ARPA, ARP Timeout 04:00:00

Last input never, output 1d23h, output hang never Last clearing of "show interface" counters never Queueing strategy: fifo Output queue 0/40, 0 drops; input queue 0/75, 0 drops

5 minute input rate 0 bits/sec, 0 packets/sec 5 minute output rate 0 bits/sec, 0 packets/sec 1 packets input, 64 bytes Received 0 broadcasts, 0 runts, 0 giants, 0 throttles 0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored

0 watchdog, 0 multicast 0 input packets with dribble condition detected

2 packets output, 424 bytes, 0 underruns

0 output errors, 0 collisions, 1 interface resets 0 babbles, 0 late collision, 0 deferred 0 lost carrier, 0 no carrier 0 output buffer failures, 0 output buffers swapped out

Switch1# sh version

Cisco Internetwork Operating System Software

IOS (tm) C2900XL Software (C2900XL-C3H2S-M), Version 12.0(5)WC8, RELEASE SOFTWAR

E (fc1)

Copyright (c) 1986-2003 by cisco Systems, Inc.

Compiled Thu 19-Jun-03 13:09 by antonino

Image text-base: 0x00003000, data-base: 0x0034E2F4

ROM: Bootstrap program is C2900XL boot loader

Switch1 uptime is 1 day, 23 hours, 31 minutes

System returned to ROM by power-on

System image file is "flash:c2900xl-c3h2s-mz.120-5.WC8.bin"

cisco WS-C2924M-XL (PowerPC403GA) processor (revision 0x11) with 8192K/1024K byt

es of memory.

Processor board ID FAA0402G17B, with hardware revision 0x03

Last reset from power-on

Processor is running Enterprise Edition Software

Cluster command switch capable

Cluster member switch capable

24 FastEthernet/IEEE 802.3 interface(s)

32K bytes of flash-simulated non-volatile configuration memory.

Base ethernet MAC Address: 00:B0:64:7F:66:80

Motherboard assembly number: 73-3425-10

Power supply part number: 34-0920-01

Motherboard serial number: FAA04019FEM

Power supply serial number: NONE

Model revision number: A0

Model number: WS-C2924M-XL-EN

System serial number: FAA0402G17B

Configuration register is 0xF

I'm really desperate here I have no idea what the problem is, and I cannot prepare for the exam without being able to assign ip addresses to the switch ports. If anyone can help me I would be EXTREMELY grateful.



Re: Can't get switch ports to work

I think it was already mentioned here, but you can not assign sw ports IP's on that switch.

New Member

Re: Can't get switch ports to work

I suspect (if you've connected router and switch directly) your router port is also down? Did you also do a no shutdown on your router ports? These are down by default, and this would cause the switchports to stay down if youre plugging in the cable.

New Member

Re: Can't get switch ports to work

yeah dood uhhh wicked embarassing why didn't I think of that, switch is layer 2 LAWL

I knew it was something simple I forgot.

Okay so I gotta put the switchports in vlans to assign IP addresses... cool thanks for the help. I took a boot camp a few months back, but I just got my homelab last week.... so a lot of the stuff I learned left me :|

Also, I dont know why, but my confreg is 0xF..... is that normal for my switch?

Thanks a lot I must've skipped over your comment earlier, my bad :P


New Member

Re: Can't get switch ports to work

Dont worry about it ;)

what the configuration register is concerned:

0xF would be normal: examine NVRAM for boot system commands, and if unsuccessful, boot the first image im flash.

please rate if it helps ;)


Re: Can't get switch ports to work

The ip address on the 2900 is strictly to manage the switch and nothing else . All routing is done via a router or a L2/3 switch . 0xf is normal for a switch.